Refrigerating apparatus



Patented Nov. 8, 1927.

UNITED STATES PATENT oFFIcE.

HARRY B. HULL, OF DAYTON, OHIO, 'ASSIGNOR TO DELCO-LIGHT COMPANY, OF DAYTON,v

' OHIO, A CORPORATION OF DELAWARE.

REFRIGERATING APPARATUS..

Original applleationled October 8,

The present invention relates to transmission mechanism and-particularly to be'lt'and v objects of the present invention is to provide belt and'pulley connections whereby under normal operating conditions, there is substanti'ally no slippage between the belt and pulleys. In case of abnormal condition of load, the belt and pulley connection is such. that slippage takes pl'ace to such an extent that the prime mover will not stall.

Another object of the present invention is to prevent burning ofthe belt in case 'of abnormal condition of load. ,One manner of carrying out the abov objects is to provide 'a substantially nonslipping driving connection between the belt and one of said pulleys and to provide for slippage between vthe belt vand the other pulley in case of abnormal condition of load. Further objects and advantages of the present invention will be :apparent from the following description, reference being made to the accompanying drawings, Awherein apreferred form of embodiment of the present invention is c'learly shown.

In the drawings:

Fig. 1 is a plan view of a refrigerator unit vembodying the present invention.

Fig. 2 is a sectional viewof the motor pnlley and drivin belt; and

Fig. 3 is a ragmentary sectional view of the compressor flywheel and driving belt.

Referring to the drawings: the refrigerator unit includes a bench 20 including a top or platform 21 supported by legs 22 at a distance above@ the floor. On the upper side ofl the platform 21 there is mounted a compressor 23, the shaft of which carries a flywheel 24 provided with a belt groove 25 fpr receiving a belt 26,which is connected with a pulley 27 operated by an electric motor 28 also mounted upon the platform 21. kProtection against the pulleys and belt is afforded by means of awire-mesh screen or pulley guard 30 secured by brackets 31 to the platform 21.

A recelver 37 is carried on the under side 1923, serial No. 666,218. Divided and this application 'mea April so, 1924. serial No. 710,131..

of theplatform 21 and its inlet opening is connected by a T 42 to which two condenser coils 43 and 44 are :connectedin parallel. The other ends of the coils 43 and 44 are connected by a T 45 to the compressor 23.

The coils 43 and 44 are suitably supported above the platform 21.

The recelver 37 vis suitably connected by a lfitting 51 to a high-pressure pipe 54' which in turn is connected .to an evaporator (not shown). -A low-pressure pipey 56 leading from the evaporator is connected with a coupling 57 to a pipe 58 whichis connected to the inlet of the compnessor 23. The coupling 57 also connects a control pipe 60, leading to a switch controller 61, with the pipes 56 and 58'. The motor28 is connected with a current source by wires 62 and 63 connected with the controller switch 61 and by a wire Gli-connecting the switch 61 with the current source. The controller 61 may be of the tylpe shown in the copending application of esse G. King', Serial No. 677,137, filed Nov. 26, 1923.

For the understanding of the present invention itis sulficient to state that when the pressure in the pipel 60 exceeds a certain value, the motor will be rendered operative to withdraw evaporated refrigerant from the evaporator, causing the same to be compressed and condensedv and. delivered back to the evaporator in somewhat liquefied condition. lhen the pressure pipe-60 fallsbethe pump is idle the refrigerant will evapv orate in the )evaporator until the pressure in pipe 60 increases again toa point wherethe motor will begin operation. Thusthe cycle of operation is repeated automatically, Y

The pulley groove 25 in the flywheel 24 is wider than but not as deep as the belt 26 which is keystone shaped in cross section as shown inV Figs. 2 and 3. Therefore, driving engagement 1s provided by the-inner surface of the belt engaging thebottom surface of the groove .25. Referring to Fig. 2, the groove provided in the motor pulley 27 is of such a width and shape that/driving engagement is with the sides of the belt 26 and not' thru the inner surface of the belt. This ar.-

rangement of the belt with the pulleys 27 should stick, the motor may keep on operate ing, sincethe belt 26'may sli) inthe belt groove with respect to the ywheel 24 or may slip o if the iiywheel. The belt 26 can be adjusted to provide for driving the pump by the motor 28under normal conditions, but

vunder abnormal conditions, such as sticking of the pump, the motor 'will not be *stalled but will be free to operate until the current is turned olf.. Since the motor cannot stall,

when there is an abnormal load, the danger of said motor burning out is removed. Fur.- thermore 1n case'the compressor or work machine is stalled, the entire belt is subjected to the same degree of slippage and the slipping is not concentrate/d at a certain part of the belt as would be vthe case if slip age was permitted at the motor pulley in w ich case the frictional engagement would cause the belt to be heated to such a degree as to cause same to burn. In the present invention, the entire belt is subjected to such frictional engagementin the event that the work machine should stall. Thus the temperature of the belt will not be raised to such a degree as to cause same to be injured. Furthermore as a portion ofthe belt is being heated, due to frictional engagement with the flywheel, the other portion thereof which is not in engagement with the pulley is bein cooled. In this manner the temperature o the beltwill not be raised to such ajdegree as to cause injury to same.

While the form of embodiment of the present invention as herein disclosed, constitutes a preferred form, it is to be under-` a driving pulley and avdriven pulley, one of csaid pulleys having a peripheral groove, and

a belt connecting said pulleys, sald' belt and said grooved pulley having drivin engagement therebetween through the si es of the belt and the side walls of the groove, the other of said pulleys having driving engagement through the inner surface of the belt.

3. A transmission mechanism comprising,

a relatively large pulley and a relatively small pulley, said small pulley having a peripheral groove anda Ibelt connecting said pulleys, said Vbelt and `said small pulley having driving engagement therebetween through the sides of the belt and the side Awalls of the groove, the other of said pulleys having driving en agement through Ithe inner surface of the elt.

LA transmission mechanism comprising, a plurality of ulleys, one of said pulleys having a perip eral groove and a belt con! lnecting said pulleys, said belt and grooved pulley havingl driving engagement therebetween throu the sides the belt and the sidewalls o the groove, the other of said pulleys havin drivin engagement through the inner sur ace of t e bel 5. In combination, a prime mover and' a machine adapted to be driven thereby; and a transmission mechanism between said prime mover and said. machine including a pulley driven by the prime mover and havin a peripheral groove, a second pulley for 'clrlvng the machine, and a belt connecting said pulleys, said belt and grooved pulley havin driving engagement ltherebetween throu the sides of the belt and the side walls of t e groove, the other of said pulleys havin ing engagement through the inner sur? the belt. v

6. A transmission mechanism comprising, a driving pulley and a driven pulley, and a belt for connecting said eys, one of said pulleys having driving engagement with the ace of drivf side edges of the belt, and the -other of said pulleys having driving engagement with the inner surface of the belt. In testimony whereof I hereto aix' my signature.

HARRY 

